1. Field of the Invention
The present invention relates to an apparatus with an abnormality determination function and a method for determining an abnormality. More specifically, the present invention relates to an apparatus with an abnormality determination function, the apparatus being capable of easily performing a self-diagnosis of an abnormality of the electrode portion in an apparatus provided with an electrode portion having at least three electrodes and to a method for determining an abnormality to easily determine an abnormality of the electrode portion.
2. Description of Related Art
As a method for inspecting (determining) an abnormality of an apparatus provided with a substrate at least a part of which is constituted of a dielectric body and an electrode disposed on the surface or in the internal portion of the dielectric body constituting the substrate, there has been used, for example, a method where pin probes are bought into contact with both the ends of a conductive pattern (e.g., electrode). Specifically, a current is applied to one pin probe, and a voltage value is detected at the other pin probe. From the detected value, a resistance value of the conductive pattern is calculated to inspect (determine) disconnection or short circuit of the conductive pattern.
However, in such a conventional inspection method, since the pin probes have to be changed according to the damage of the conductive pattern due to the contact of the pin probes or according to the pitch of the conductive pattern, the method is very troublesome as an inspection method. Therefore, there is disclosed a method where an alternating-current signal is applied to a conductive pattern from a feed electrode subjected to capacity coupling (also referred to electrostatic coupling) with an end of the conductive pattern to detect a signal with two kinds of sensor electrodes capacity-coupled with the other end of the conductive pattern, thereby inspecting the state of the conductive pattern on the basis of the detected signal (see, e.g., JP-A-2002-365325).
In addition, as a conductive pattern inspection apparatus capable of easy inspection with high reliability, there has been suggested a conductive pattern inspection apparatus having a sensor electrode electrostatic-coupled with an end of the pattern to be inspected and a feed electrode electrostatic-coupled with the other end of the conductive pattern to detect a value of a current flowing between the power source and the sensor electrode with applying an alternating-current signal to the pattern via the feed electrode and the sensor electrode, thereby detecting presence/absence of disconnection or short circuit of a conductive pattern (see, e.g., JP-A-2005-24518).
However, the aforementioned conductive pattern inspection apparatus described in JP-A-2005-24518 has a problem of very complex constitution of the apparatus because the current value is measured by moving the sensor electrode sequentially with respect to the conductive pattern (e.g., electrode).
In addition, as the apparatus having a conductive pattern as the electrode, there is a particulate matter detection apparatus for detecting particulate matter (PM) such as soot contained in, for example, flue exhaust gas or diesel engine exhaust gas. However, since such a particulate matter detection apparatus is sometimes very small and therefore has a problem of having much difficulty in employing the constitution described in JP-A-2005-24518 from the viewpoint of the constitution of the apparatus.